The influence of ion-implantation on the effective Schottky barrier height of NiGe/n-Ge contacts

Abstract

The mechanism for modulating the effective Schottky barrier height of NiGe/Ge contacts by incorporating impurities is still under debate. There is a view that impurities segregated at the NiGe/Ge interface act as donors or passivators that alleviate the Fermi-level pinning effect so as to significantly affect the electrical characteristics. Our study, however, clearly demonstrates that ion implantation damage is the primary factor in causing the lowering of the effective Schottky barrier, for NiGe/n-Ge contacts doped with Se or Si, although passivation behavior is observed for P doping.